Method of forming a package



Dec. 7, 1965 o. E. SEIFERTH ETAL 3,221,692

METHOD OF FORMING APAGKAGE Original Filed Oct. 29, 1959 2 Sheets-Sheet 1 fit/m,

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Q, E. SEIFERTH ETAL 3,221,692

METHOD OF FORMING A PACKAGE Dec. ,7, 1965 Original'Filed Oct. 29, 1959 2 Sheets-Sheet 2 mmvroas. Dacwlieaarfla BY Glenn/y Mi /z, M Ma W United States Patent 3,221,692 METHOD or FORMING A PACKAGE Oscar E. Seiferth and Glenn M. Austin, Madison, Wis,

3 Claims. or. 113-120 This application is a division of our application, Serial No. 849,478, filed October 29, 1959, and now abandoned.

This invention relates to packing and is more particularly concerned with improvements in a package which is especially suitable for enclosing foods so that they can be displayed in a sanitary and appealing manner and which will preserve the contents while stored preparatory to its use.

It is a general object of the invention to provide a food package which affords maximum protection to the contents while displaying the same in an attractive and appealing manner, which will preserve the food against spoilage for a substantial period, and which is of such a nature that it is readily adaptable to production packaging methods.

It is a more specific object of the invention to provide a package for food or similar products which is characterized by a container adapted to be preformed of relatively light material into relatively shallow tray-like form and provided with an outwardly stepped flange around the periphery thereof which permits the container to be supported in the open upper end of an upright hollow form for a seaming operation with a transparent covering sheet and an apertured covering disc, the latter having a seaming flange formation which cooperates with the stepped flange on the container so as to facilitate the formation of a crimped or rolled seam for securing the flange on the container with the marginal portions of the covering sheet and the seaming flange formation on the disc.

It is another object of the invention to provide a method of forming a packaging receptacle of tray-like form and a lid therefor from a single piece of relatively thin gauge sheet metal which comprises die stamping the sheet to form an open top tray structure with a top edge which has an outwardly directed stepped flange formation, cutting on a line at the inner edge of said stepped flange formation and separating the apertured lid member so formed from the remainder of the tray structure, and further die stamping the tray to provide a receptacle having a stepped flange on the edge thereof with a cross section corresponding to the cross section of the flange on the lid member whereby the lid member may be positioned on the receptacle with the flange formations in superimposed relation for forming a connecting seam.

It is still another object of the invention to provide a method of forming a packaging receptacle of traylike form and a top closure member therefor from a single piece of relatively thin gauge sheet metal which comprises die stamping the sheet to form an open top tray structure with a top edge having an outwardly directed stepped flange thereon, cutting on a line at the inner edge of the stepped flange and separating the apertured top closure member so formed from the remainder of the tray structure, and further die stamping the remainder of the tray structure to provide a receptacle of pie pan shape having a stepped flange corresponding substantially to the shape of the flange on the closure member whereby the closure member may be positioned on the receptacle with the flanges in interengaged relation for forming a connecting seam by a crimping operation.

3,221,692 Patented Dec. 7, 1965 It is a further object of the invention to provide a method of forming a package of a food product which comprises providing a receptacle of relatively thin gauge deformable material which is preformed to provide a pie pan shape and a stepped flange at the edge thereof, filling the receptacle with a quantity of the product to be packaged, supporting the filled receptacle in the upper end of an upright hollow cylindrical form which has a relatively narrow top edge on which an inner flange portion of the stepped flange on the receptacle is seated, placing a sheet of transparent plastic film over the open top of the filled receptacle, placing a closure member of deformable material thereon which closure member is preformed to provide an apertured center portion and an edge flange portion which nests with the stepped flange on the receptacle and crimp sealing the outermost portions of the flanges while the assembly is supported on said form.

These and other objects and advantages of the invention will be apparent from a consideration of the package and the method of forming the same, which are illustrated in the accompanying drawings wherein:

FIGURE 1 is a perspective view of a completed package which embodies therein the principal features of the invention;

FIGURE 2 is a fragmentary section taken on the line 2-2 of FIGURE 1 to an enlarged scale;

FIGURE 3 is an exploded sectional view showing the packaging elements arranged above a tubular support member on which the package elements are supported while a connecting seam is formed;

FIGURE 4 is a fragmentary section, to an enlarged scale, on a diameter of the support member with the package elements assembled thereon in proper relationship for forming the crimped seam at the top margin of the package;

FIGURE 5 is a fragmentary section similar to FIGURE 4 with the support member and the package elements clamped in the final position in which the crimped seam is completed;

FIGURES 6 to 10 illustrate a method of forming certain of the packaging elements from a single sheet of stock material; and

FIGURE 11 is a fragmentary section, similar to FIG- URE 4, illustrating a modification in the seam forming elements.

The package as illustrated particularly in FIGURES 1 and 2 of the drawings comprises a quantity of a product 10 which may be a food, such as, liver sausage, chili con carne, cheese or the like, supported in a bottom container 11 which is of tray-like or pie pan form. The container 11 is preformed of a relatively light sheet material and comprises a bottom wall 12, an upwardly and outwardly slanting peripheral wall section 13 which terminates at its top edge in an outwardly directed stepped flange formation 14. The flange formation 14 includes an inner flange 15 which is in a plane parallel with the bottom wall 12, an upwardly and outwardly slanted peripheral Wall section 16 and an outwardly extending seaming flange 17, which, as shown in FIGURE 2, is coiled into tight seam forming relation with a cooperating outwardly extending flange formation 18 on a seam forming ring 20. The seaming ring 20 has a narrow inwardly directed flange portion 21 which is adapted to be seated on the inner flange 15 of the container 11. A sheet of transparent film material 22 is interposed between the container 11 and the closure or seam forming ring 20 so as to cover the entire open top of the container 11, the marginal portion 23 of the cover sheet 22 being reversely coiled about the ends of the seaming flange formation 17 and 18 so that it is tightly clamped between the same when the seaming operation is completed.

The package, as illustrated, is especially adapted for use in the marketing of food products but it may be used for other products of a similar nature where it is desirable that the product be enclosed in an hermetically sealed package formed of material which are impervious to the transmission of moisture, flavor and the like, and which Permit at least a portion of the product to be viewed. The package is suitable for any product for which it is desirable to provide airtight protection so as to preserve the product against spoilage or deterioration for a substantial period of time. Also, it is particularly suitable for packaging an uncooked food product which it may be convenient to prepare, or process, while it is in the package, by boiling in water or the like. With such a product, the consumer may cook the material immediately upon receiving the package or the package may be stored for a period of time and then subjected to the cooking process.

The container 11 may be performed from various materials, depending upon the nature of the product which is to be packaged. For products of a type in which only a portion of the product need be displayed, the container 11 is preferably formed of a relatively thin or light gauge aluminum so as to enable it to be economically manufactured with little material. The container 11 may, however, be preformed of a plastic sheet or film of the type which is hereinafter referred to as suitable for the cover sheet 22.

The sealing ring 20 is fabricated of a material of such a nature that it will permit a crimped seam to be formed with the peripheral edge portion thereof which forms the seaming flange 18 being coiled during the seaming operation. It is preformed or preshaped, preferably, from a relatively light gauge steel or aluminum sheet material. As illustrated, the sealing ring 20 has its center portion removed so as to permit the contents of the package to be observed through the transparent covering film 22 which cooperates with the ring 20 in forming the cover for the open top of the container 11. The removal of the center portion leaves the sealing ring 20, as initially formed, with a relatively narrow inner flange 21 Which extends inwardly from the generally cylindrical wall section 24, the latter constituting the inner side of the outwardly extending inverted channel shaped seaming flange portion 18 which has its outer side 25 curved downwardly and inwardly, as shown in FIGURES 3 and 4.

The covering sheet 22 is preferably a plastic film material having a low gas transmission, such as, Mylar, (an oriented linear polyester resin). The cover sheet 22 may, however, be formed of other plastcs having similar characteristics such as Saran (a vinylidene chloride polymer), vinyl, polyethylene and cellulose acetate, for example. While the cover sheet 22 is preferably thin and flexible, it may be of a semi-rigid nature. Any combination of the plastics referred to may be employed as a covering sheet for example Saran coated Mylar, the selection of the same being dependent upon the character of the product which is to be enclosed in the package.

, In forming the package the container 11 and the sealing ring 20, which are preshaped or preformed to provide them with the cross section illustrated in FIGURES 3 and 4, are assembled with a predetermined quantity of the product on a support or form 26 and the seaming operation is accomplished in a conventional can closing machine. A series of upright traveling forms 26, which are in the nature of tubular sections, are provided for receiving the package assembly. The internal diameter of each form 26 is approximately the same as the external diameter of the container 11 at the junction of the stepped flange formation 14 with the body or side wall 13 of the container, so that, when the container 11 is filled with the product 10 which is being packaged, the

filled container may be supported in the open upper end of the form 26 with the upper edge portion 27 of the form 26 engaging the bottom surface of the inner flange 15 and the remainder of the flange formation 14 extending radially outwardly of the outer peripheral surface of the form 26. The cover sheet 22 is then positioned over the top of a container 11 with the marginal portions 23 thereof draped over the seaming flange 17, as shown in FIGURE 4, after which the sealing ring 20 is positioned so that the sealing flange 17 on the container 11 is seated in the downwardly facing channel which is provided by the seam forming portion 18 of the sealing ring 20. This brings the inwardly directed flange 21 of the sealing ring 20 into posiiton above the inner flange 15 of the container 11 so that when the assembly is moved into proper position relative to the seaming head of the closing machine the holding fixture or clamp 28 will move into clamping position as shown in FIGURES 4 and 5 and the assembly will be clamped between the lifter plate 30 on which the form 26 is supported and the holding fixture 28 for the seaming operation by the seaming or curling roll '31 which are carried on the rotating seaming head of the canning machine. The seaming rolls 31 move in against the seaming flange assembly as the seaming head rotates and form the seam by rolling the assembled flanges downwardly and into coiled relation as shown in FIGURE 5. The seaming rolls 31 carry a cutting blade or knife edge 32 at the lower terminus of the seaming groove 33 which trims the excess material from the marginal portion 23 of the cover sheet 22. When the seaming operation is completed the assembly is removed from the canning machine and the completed package is lifted out of the form 26. Preferably, the canning machine is a vacuum type and the seaming operation is carried out in a closed chamber under vacuum.

The container 11 and the sealing or seam forming ring 20 may be of the same materials and preferably are formed from a single sheet of stock material as illustrated in FIGURES 6 to 10. The sheet 35 (FIGURE 6) will be selected from stock of the proper gauge to give the desired thickness in the walls of the container 11 and the sealing ring 20 after the preforming operation. The sheet 35 is drawn or shaped between a pair of dies (not shown) to provide the open top cup or pan-like container 36 (FIGURE 7) with a peripheral flange formation 37 which preferably is drawn to provide the cross section of the ring 28 (FIGURE 8). The flange section 37 is then separated from the body 36 on the cutting line indicated at 38 leaving the completely preformed sealing ring 20 and the body portion 36. The latter is then subjected to a second forming operation between a pair of suitable forming (lies (not shown) to provide the pie pan shaped container 11 as shown in FIGURE 10 with the peripheral stepped flange formation 14 which has been described. This procedure for forming the sealing ring 20 and the pan-like container 11 provides an economical method of obtaining these two package elements from a minimum of stock material with a minimum of forming or drawing operations. This procedure is followed in preparing the pan and ring elements when these two elements are formed of the same material, such as, light gauge aluminum or steel.

The sealing ring 20 may be provided with a suitable sealing or gasket material 41, as illustrated in FIGURE 11, in the downwardly facing channel-like pocket formed in the seaming flange formation 18 which will serve as a friction ring to grip the plastic cover sheet 22 and more securely hold the same in proper position for forming the rolled or crimped seam and which may also serve as a sealant for increasing the effectiveness of the seam. Several such materials are known and used commercially. For example, the gasket material may be a rubber base gasket emulsion.

The shape of the package is not limited to that shown in the drawings. The tray-like container may be any shape having rounded or radially determined corners so that a closure seam may be formed by crimping or rolling the flanges of the tray and the top closure members, the latter being, of course, formed with flanges which mate with the flanges on the tray, for example, it may be oval or it may be rectangular with rounded corners.

While particular materials and specific details of construction have been referred to in describing the illustrated form of the package and the method of forming the same, equivalent materials and details of construction may be resorted to within the spirit of the invention.

We claim:

1. A method of forming a receptacle of tray-like form and a lid therefor from a single piece of relatively thin gauge metal sheet which comprises drawing the sheet between a pair of dies which are shaped to form the sheet into an open top pan-like container body portion having a bottom wall and an upwardly extending side wall with a peripheral upper edge portion which comprises inwardly and outwardly directed flange formations in vertically spaced planes and a connecting, upwardly and outwardly slanted narrow peripheral wall section, cutting the drawn sheet at the top edge of the body side wall and separating said peripheral edge portion from the container body forming portion to provide an apertured lid and further drawing the top margin of the side wall of the body portion to provide thereon inwardly and outwardly directed, vertically spaced flange formations and a connecting, upwardly and outwardly slanted, narrow wall section, with the respective flange formations and the connecting wall section on the body portion each having a slightly larger diameter than the corresponding flange formations and connecting wall section on the lid so that the lid may be placed on the body portion with the flange formations and connecting wall section thereof in superimposed nested relation with the flange formations and connecting wall section on the body portion.

2. A method of forming a receptacle of tray-like form and a closure lid therefor from a single piece of relatively thin gauge metal sheet which comprises drawing the sheet between a pair of dies which are shaped to form the sheet into an open top pan-like container body forming portion having a bottom wall and an upwardly extending side wall with a narrow peripheral upper edge portion of the side wall including flange formations in vertically spaced planes and extending inwardly and outwardly of a narrow connecting wall section which wall section extends upwardly of the outer edge of the lowermost flange formation, cutting the drawn sheet at the inner edge of the lowermost flange formation and separating said peripheral edge portion from the container body forming portion to provide an apertured closure lid, and drawing the top portion of the side wall of the remainder of the body portion to form thereon vertically spaced flange formations which extend inwardly and outwardly of a narrow vertical connecting wall section which wall section extends upwardly of the outer edge of the lowermost one of said flange formations, the respective body flange formations and the body wall section which connects said body flange formations having a diameter slightly larger than the diameter of the corresponding flange formations and wall section of the lid member so that the lid member may be placed on the body portion with the flange formations and connecting wall section thereof in surface engaging and nested relation with the flange formations and connecting wall section on the body forming portion.

3. A method of forming a receptacle of tray-like form and a lid therefor from a single piece of relatively thin gauge sheet metal which comprises drawing the sheet between a pair of dies so as to form an open top tray structure with a bottom wall and an upstanding side wall which is shaped at the top margin into a narrow edge formation providing in cross section narrow flange portions which extend outwardly of the tray side wall and are stepped upwardly with a narrow connecting wall portion, cutting on a line at the inner edge of the innermost flange portion and separating the apertured lid member thus formed from the body forming remainder of the tray, and further drawing upper marginal portions of the side wall of the remainder of the tray to provide on the top thereof a narrow edge formation providing in cross section narrow flange portions which extend outwardly of the tray side wall and are stepped upwardly with a narrow connecting wall portion which flange portions and connecting wall portion have a cross section corresponding to the cross section of the corresponding flange and wall portions of the lid member and which are slightly larger in diameter so that the lid member may be positioned on the body with the flanges and connecting wall portions in nested relation.

References Cited by the Examiner UNITED STATES PATENTS 1,837,886 12/1931 Schmidt 113-416 1,884,699 10/1932 Hothersall 113-116 2,089,972 8/1937 Lyon 1131 16 2,253,499 8/1941 Rutenber 1131 16 CHARLES W. LANHAM, Primary Examiner. NEDWIN BERGER, Examiner. 

1. A METHOD OF FORMING A RECEPTACLE OF TRAY-LIKE FORM AND A LID THEREFOR FROM A SINGLE PIECE OF RELATIVELY THIN GAUGE METAL SHEET WHICH COMPRISES DRAWING THE SHEET BETWEEN A PAIR OF DIES WHICH ARE SHAPED TO FORM THE SHEET INTO AN OPEN TOP PAN-LIKE CONTAINER BODY PORTION HAVING A BOTTOM WALL AND AN UPWARDLY EXTENDING SIDE WALL WITH A PERIPHERAL UPPER EDGE PORTION WHICH COMPRISES INWARDLY AND OUTWARDLY DIRECTED FLANGE FORMATIONS IN VERTICALLY SPACED PLANES AND A CONNECTING, UPWARDLY AND OUTWARDLY SLANTERD NARROW PERIPHERAL WALL SECTION, CUTTING THE DRAWN SHEET AT THE TOP EDGE OF THE BODY SIDE WALL AND SEPARATING SAID PERIPHERAL EDGE PORTION FROM THE CONTAINER BODY FORMING PORTION TO PROVIDE AN APERTURED LID AND FURTHER DRAWING THE TOP MARGIN OF THE SIDE WALL OF THE BODY PORTION TO PROVIDE THEREON INWARDLY AND OUTWARDLY DIRECTED, VERTICALLY SPACED FLANGE FORMATIONS AND A CONNECTING, UPWARDLY AND OUTWARDLY SLANTED, NARROW WALL SECTION, WITH THE RESPECTIVE FLANGE FORMATIONS AND THE CONNECTING THE WALL SECTION ON THE BODY PORTION EACH HAVING A SLIGHTLY LARGER DIAMETER THAN THE CORRESPONDING FLANGE FORMATIONS AND CONNECTING WALL SECTION ON THE LID SO THAT THE LID MAY BE PLACED ON THE BODY PORTION WITH THE FLANGE FORMATIONS AND CONNECTING WALL SECTION THEREOF IN SUPERIMPOSED NESTED RELATION WITH THE FLANGE FORMATIONS AND CONNECTING WALL SECTION ON THE BODY PORTION. 